Is a mistake of law a defense of ignorance of the law?

"A mistake of law, in its strict sense, means ignorance that the penal law (of which one stands accused) prohibits one's conductand ignorance on this point 'is almost never a defense.' " (People v. Meneses (2008) 165 Cal. App.4th 1648, 1662-1663.) Thus, "[i]t is commonly said that ignorance of the law is no excuse." (People v. Zamani (2010) 183 Cal.App.4th 854, 887.) "There are a number of circumstances, however, in

Page 11

which violation of a penal statute is premised on the violator's harboring a particular mental state with respect to the nonpenal legal status of a person, thing, or action. In such cases, the principle is 'firmly established that defendant is not guilty if the offense charged requires any special mental element, such as that the prohibited act be committed knowingly, fraudulently, corruptly, maliciously or wilfully, and this element of the crime was lacking because of some mistake of nonpenal law.' . . . Thus, a taxpayer may defend against a [tax fraud] charge on the basis, for example, that he mistakenly believed certain deductions were proper under the tax laws, but not on the basis that he was unaware it was a crime to lie on one's tax return." (People v. Hagen (1998) 19 Cal.4th 652, 660, fn. 4.) Courts also have permitted a "defense of ignorance of the law" in cases involving "prosecution under complex regulatory schemes that have the potential of snaring unwitting violators." (United States v. Fierros (9th Cir. 1982) 692 F.2d 1291, 1295 (Fierros).)

b. Mistake of Nonpenal Law